[CQ-Contest] World Wide Digi DX Contest Results.

[Tim Shoppa]

I was a vigorous participator in the CQ WW Digi and have some thoughts
about the high NIL rate.

First of all - I was not at all surprised. I work with some DXpedition QSL
managers and they have been complaining about the incredibly high NIL rate
seen with DXpeditions in FT8 mode for a while now.

In CW, SSB, or RTTY there is (at the 99% accuracy level) a "meeting of
minds" over the air as to whether the QSO was complete or not on both
sides. Part of it the fraction of a second it takes in these modes to send
a "thanks" or "TU" before moving to the next caller. Another part is that a
human actually makes the call on each end as to whether it was complete
using the human's best judgement, and the cycle time it takes to be sure is
infinitesimal (just seconds, not a 30-second cycle).

In FT4/FT8 this meeting of minds is far more slippery and tenuous. This is
completely inexplicable to those who have drunk the FT8 Kool-Aid because
they trust the computer for all aspects of a QSO. As a result the FT4/FT8
NIL rate (even with DXpeditions) is far far higher than the traditional
modes. Adding a whole additional transmit/receive cycle for an extra level
of confirmation may not actually improve things but make it worse because
if reception is lost by one side but not the other in that extra cycle that
itself will lead to more NIL's.

Tim N3QE